Gas turbine engine components such as bearings require continuous lubrication provide cooling and lubrication due to high operating temperatures, pressures, and friction. Oil is distributed to these components throughout the engine in a series of tubes. For example, a bearing housing may receive oil from a transfer tube connected to a plenum with multiple feed lines and nozzles. Oil transfer tubes and seals are subject to high stresses and torque in addition to the high temperatures and pressures, which can lead to premature leakage and failure. When a leak occurs in the vicinity of hot engine parts, the oil can coke up and catch fire, necessitating unscheduled replacement and repair of the entire engine.
It is relatively easy for technicians to overtorque oil transfer tubes when trying to retighten a tube to fix or prevent oil leaks. When the tube is overtorqued, it becomes difficult or impossible to remove due in part to extrusion of the copper seal material between the threads at the seal interface. Thus it would be helpful to provide a transfer assembly that simultaneously prevents or discourages overtorquing while still minimizing leaks.